The present invention relates to electrical utility boxes for wall outlets and wall switch installations.
Outlet and switch connections have conventionally been made in a junction box which is fastened to a stud of the building prior to the application of plaster, or in more recent times, the installation of wallboard. A main cable is laid up to the junction box and the end is stripped, the ends of the individual wires are stripped, and the ends inserted through an opening in the junction box. A similar operation generally must be performed on the end of a second cable which leads from the first junction box to another box more remote from the power supply, and if the junction box is to house a switch rather than an outlet, or an outlet controlled by a switch, yet a third cable must be installed to connect with the load or the switch.
After the wallboard has been installed and a hole cut, the stripped wires are pulled through the hole and fastened to the terminals of the switch or outlet. The fastening generally involves the bending of the individual bared wires around screw terminals and the tightening down of the screws to make a secure connection. This procedure is tedious and time consuming, and with the present-day high cost of labor and increased demands for convenience outlets and switches, is expensive as well.
Outlets have been developed which accelerate the installation process such as the devices represented in U.S. Pat. Nos: 2,946,838, 3,160,458 and 3,218,596. These devices represent improvements over the older outlets but nonetheless either involving the use of screw connections or connectors which fail to securely hold the wires in place or make sound electrical contact.
Another troublesome aspect of present utility box installation is the difficulty of mounting the box such that the front surface is flush with the finished wall, a problem because the utility box must be mounted prior to the installation of the wall. Although the problem was more serious prior to the widespread use of wallboard of fairly uniform thickness, proper allignment still requires careful measurement during installation, the procedure being further complicated by the several thicknesses in which the wallboard is produced. A testimonial to the reality of the problem is found in U.S. Pat. No. 1,961,728, which discloses an outlet box with front edges which are easily broken off, eliminating the need for careful measurement.